I. Field of the Invention
The present invention relates to a method and an associated device for modifying a sound-volume value of an acoustic alert signal emitted on command on board an aircraft.
II. Description of Related Art
In an aircraft cockpit, the flight warning system (or alarm calculator) is intended to forewarn the crew members of an abnormal situation concerning monitored systems of the airplane, which may include detectors or calculators relating, for example, to the engines or fuel tanks.
The acoustic signals generated in the cockpit by the warning system, known as acoustic warnings and intended to forewarn the crew of an abnormal situation, may comprise diverse sounds, voice syntheses or a mix of sounds and voice syntheses (known as “hybrid” mixes).
Diverse technologies exist for flight warning systems. The on-board systems are generally constructed on the basis of specific electronics integrated into the airplane (embedded systems).
In the Airbus A320 and A330/A340 family, for example, the alarm system is a unit that can be replaced on-line (LRU for “Line Replaceable Unit” and is known as “Flight Warning Computer” (flight warning computer). In the A380 and A400M family, the alarm system is a software program known as “Flight Warming Application” (flight warning application), executed by modules that can be replaced on-line (LRN for “Line-Replaceable Module”), which integrate the integrated modular avionic technology (IMA: “Integrated ModularAvionics”).
The industrial development of an aircraft warning system passes through the finalization of a system standard (ready-to-use version serving as reference, or de facto standard applicable to different participants in the aircraft development process as well as to the users). The production of a new on-board system standard involves numerous industrial participants as well as extensive logistics, and it is therefore costly.
In addition, if an alarm system is to be installed in a commercially operated airplane, it must be certified by certification authorities. During the industrial phase of mass production of the airplane, a warning system standard is certified approximately every year.
When such an alarm system generates a sound level that is too faint, it can cause the crew to misunderstand or misinterpret an abnormal or emergency situation.
Conversely, a sound level that is too loud may represent a nuisance for the members of the crew while they perform their tasks.
When this type of situation is observed, for example by a crew in the course of a development or operational phase, in connection with one or more acoustic warning signals, the solution currently used to correct the inappropriate sound level is to design a new alarm system standard that integrates the readjusted sound levels. In addition, the new alarm system standard must then be certified, thus imposing further delays.
The manufacturers and the airline companies are therefore confronted with the problem of the length of delays necessary for adjustment of the sound level of acoustic warnings.
This problem is exacerbated by the technical complexity and the lack of flexibility of the current methods.